1 /**
2 * This file Copyright (c) 2008-2015 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.module.cache.filter;
35
36 import info.magnolia.cms.cache.CacheConstants;
37 import info.magnolia.cms.filters.AbstractMgnlFilter;
38
39 import java.io.IOException;
40
41 import javax.servlet.FilterChain;
42 import javax.servlet.ServletException;
43 import javax.servlet.http.HttpServletRequest;
44 import javax.servlet.http.HttpServletResponse;
45
46 /**
47 * <p>
48 * Filter that sets cache headers, allowing or dening cache at client-side. By default the filter adds the "Cache-Control: public" and expire directives to resources so that everything can be cached by the browser. Setting the <code>nocache</code> property to <code>true</code> has the opposite effect, forcing browsers to avoid caching.
49 * </p>
50 * <p>
51 * The following example shows how to configure the filter so that static resources (images, css, js) gets cached by the browser, and deny cache for html pages.
52 * </p>
53 *
54 * <pre>
55 * + server
56 * + filters
57 * + ...
58 * + headers-cache
59 * - class info.magnolia.module.cache.filter.CacheHeadersFilter
60 * - expirationMinutes 1440 <em>(default)</em>
61 * + bypasses
62 * + extensions
63 * - class info.magnolia.voting.voters.ExtensionVoter
64 * - allow gif,jpg,png,swf,css,js
65 * - not true
66 * + headers-nocache
67 * - class info.magnolia.module.cache.filter.CacheHeadersFilter
68 * - nocache true
69 * + bypasses
70 * + extensions
71 * - class info.magnolia.voting.voters.ExtensionVoter
72 * - allow html
73 * - not true
74 * </pre>
75 *
76 * @deprecated since 5.4. Use {@link info.magnolia.module.cache.executor.SetExpirationHeaders} instead.
77 */
78 public class CacheHeadersFilter extends AbstractMgnlFilter {
79
80 /**
81 * Number of minutes this item must be kept in cache.
82 */
83 private long expirationMinutes = 1440;
84
85 /**
86 * Cache should be avoided for filtered items.
87 */
88 private boolean nocache;
89
90 /**
91 * Sets the expirationMinutes.
92 *
93 * @param expirationMinutes the expirationMinutes to set
94 */
95 public void setExpirationMinutes(long expirationMinutes) {
96 this.expirationMinutes = expirationMinutes;
97 }
98
99 /**
100 * Sets the nocache.
101 *
102 * @param nocache the nocache to set
103 */
104 public void setNocache(boolean nocache) {
105 this.nocache = nocache;
106 }
107
108 @Override
109 public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
110 if (nocache) {
111 response.setHeader(CacheConstants.HEADER_PRAGMA, CacheConstants.HEADER_VALUE_NO_CACHE);
112 response.setHeader(CacheConstants.HEADER_CACHE_CONTROL, CacheConstants.HEADER_CACHE_CONTROL_VALUE_DISABLE_CACHE);
113 response.setDateHeader(CacheConstants.HEADER_EXPIRES, 0L);
114 } else {
115 response.setHeader(CacheConstants.HEADER_CACHE_CONTROL, CacheConstants.HEADER_VALUE_MAX_AGE + "=" + expirationMinutes * 60 + ", " + CacheConstants.HEADER_VALUE_PUBLIC);
116 final long expiration = System.currentTimeMillis() + expirationMinutes * 60000;
117 response.setDateHeader(CacheConstants.HEADER_EXPIRES, expiration);
118 }
119
120 chain.doFilter(request, response);
121 }
122 }